Effect of the reagent vibration on stereodynamics of the reaction O（^1D）＋HF→F＋OH

This paper studies the influence of the reagent vibration on the reaction O(¹D)+HF → HO+F by using a quasi-classical trajectory method on the new \textitab initio ¹A' ground singlet potential energy surface (Gómez-Carrasco et al 2007 Chem. Phys. Lett. 435 188--193). The product angular distributions which reflect the vector correlation are calculated. Four polarization-dependent differential cross sections (PDDCSs) which are sensitive to many photoinitiated bimolecular reaction experiments are presented in the center of the mass frame, respectively. The differential cross section indicates that the OH product mainly tends to the forward scattering, and other PDDCSs are also influenced by the vibration levels of HF.     

Influence of laser fields on the vibrational population of molecules and its wave-packet dynamical investigation

The time-dependent wave packet method is used to investigate the influence of laser-fields on the vibrational population of molecules.For a two-state system in laser fields,the populations on different vibrational levels of the upper and lower electronic states are given by wavefunctions obtained by solving the Schro¨dinger equation with the splitoperator method.The calculation shows that the field parameters,such as intensity,wavelength,duration,and delay time etc.can have different influences on the vibrational population.By varying the laser parameters appropriately one can control the evolution of wave packet and so the vibrational population in each state,which will benefit the light manipulation of atomic and molecular processes.     

Investigation of isotope effects of dynamic properties for H(D) +OF reactions by the quasi-classical trajectory method

Quasi-classical trajectory (QCT) calculations are employed to study the dynamic properties for \mbox{H(D)} + \mbox{OF} reactions on the adiabatic potential energy surface (PES) of the \mbox{1}{ }^{3}\mbox{A}' triplet state. Obvious differences between the reaction probabilities for J = 0, integral cross sections for J \ne 0, branch ratios of the product and internuclear distances as well as product rotational alignments between the title reactions are found. These differences are attributed mainly to the different reduced masses of the reactants and the different zero-point energies (ZPEs) of the transition state.     

基于Faster R-CNN和数据增强的棉田苗期杂草识别方法

为解决棉花幼苗与多种类杂草交叉生长的识别率低、鲁棒性差等问题,以棉花幼苗和田间的七类常见杂草为研究对象,提出了一种基于Faster R-CNN和数据增强的棉田苗期杂草识别方法.采集不同背景下受光照影响的杂草图像4694张,包括晴天、阴天和雨天.通过对样本图像的数据增强和特征提取网络ResNet-101的参数优化,训练出...     

极坐标堆焊沉积成型插补控制算法研究

本文介绍了极坐标运动轨迹控制在堆焊增材制造中的优势,研究了极坐标直线插补和圆弧插补算法,采用三次多项式拟合各轴的速度曲线,结合位置伺服解决了逐点比较法中的悬臂摆振问题,通过实验对比发现极坐标插补在堆焊快速成型方面与直角坐标插补效率相当,结合机械回转填充方式能避免传统直角坐标方式的插补计算带来的响应滞后.最后与极坐标逐点比较法进行对比测试,验证了成型控制软件的执行效率,发现当插补精度为0.04mm时,可获得较好的成型精度与响应时间.     

基于掺杂氟的二氧化锡导电玻璃的苏丹红I号电化学降解研究

研究了基于掺杂氟的二氧化锡(FTO)导电玻璃的苏丹红I号电化学降解工艺,考察了电解质浓度、环境酸度、外加电压、初始浓度等因素对苏丹红I号去除率的影响.结果表明,以FTO导电玻璃为阳极,控制电解电压为12 V,对含20 g/L氯化钠的苏丹红I号(0.01 g/L)溶液(p H 9.0)进行电化学降解20 min后,苏丹红I号的脱色率可达到60%.     

碰撞能和同位素取代对H+BrF→HBr+F反应立体动力学影响的理论研究

基于拟合得到的London-Eyring-Polanyi-Sato势能面,运用准经典轨线方法对H+BrF→HBr+F反应的立体动力学性质进行了理论研究.计算了反映矢量相关的角分布和对光诱导的双分子反应实验敏感的四个极化微分散射截面.结果表明:随着碰撞能的增加,产物的转动极化变强,并且产物的后向散射占主导地位.通过比较D+BrF→DBr+F和H+BrF→HBr+F反应的产物极化,揭示了明显的同位素效应.     

LNG储罐日蒸发率测量方法及计算

日蒸发率是衡量LNG储罐绝热性能的重要指标,有效了解储罐日蒸发率,将有利于LNG储罐安全运行的维护。结合储罐日蒸发率的定义和标准,根据实际操作情况,给出了几种测量LNG储罐日蒸发率的方法及其计算公式,并论述了各种测量方法的适用性和工艺条件。     

WAVE技术在减速器参数化设计中的应用

对UG/W AVE技术的主要内容及其技术内涵进行了简要的阐述,并以减速器设计为例,介绍了如何利用W AVE技术实现产品模型设计过程中的参数化设计方法.     

共振原理在音乐艺术中的应用

共振原理在音乐艺术中的应用收稿日期：１９９７年１１月３日许燕（广西师大桂林５４１００１）音乐艺术离不开“共振”。无论是声乐还是器乐，共振都在其中起着决定性的作用，甚至可以这样说，没有共振就没有音乐。琴弦的音调是由琴弦的振动频率所决定的，并由琴弦与共...